This patent basically explains a new adapter for mirrorless that would sit in between the camera and the lenses.

This adapter would have the ability to silently change the ND filter value to eliminate aperture opening / closing noise during video recording.

It would also allow for the use of very fast lenses with a dynamic method of controlling the amount of light received by the camera without stopping down the lens.

Supply chain sources have said in the past that Canon can sometimes bring two versions of a product to “production ready” and then basically decide at the last minute which one will get produced. This could be the case with the two rumored camera bodies currently in testing.

A variable ND filter would be a killer product! I would assume it would have a mode switch built in for ND or iris.The other feature it needs is the ability to be manually controlled from the +/- EV settings. Besides not having to carry a set of ND filters, it would make the use of front mounted filters so much easier. Shooting flowing water or motion blurring clouds will be much more enjoyable. I can't tell you how many times I've stopped to change filters while shooting in Yosemite. Just the time saved would make this a great addition to the bag. If Canon is smart, the FF mirrorless bodies will use an adapter for EF lenses, allowing this variable ND technology.